Mr Evans was appointed chief executive of the Invercargill bank in August 2014, replacing Ross Smith, who had been in the top role for 22 years.
It is understood Mr Evans (49) died on Wednesday in Queenstown but a spokesman for the bank would not make further comment other than issuing a statement in the name of chairman John Ward.
Mr Evans was a vibrant and respected leader of SBS, Mr Ward said.
"His passion and strategic leadership will be acutely missed.
"Our heartfelt condolences go to Wayne's family.''
Mr Evans was educated at Southland Boys' High School before completing a bachelor of commerce (accounting) degree at the University of Otago and a postgraduate diploma in psychology at Massey University. He returned to Invercargill to establish the SBS subsidiary Finance Now.
Mr Evans worked in the health sector, for ANZ bank and headed a company which ultimately became GE Money.
Becoming frustrated with dealing with an offshore head office, he suggested to a colleague they might do better on their own.
He approached then SBS chief executive Mr Smith and the SBS board agreed to start a finance company, Finance Now, based in Invercargill.
Long-distance swimming was a large part of Mr Evans' life, and in 2013 he became the seventh person to swim Foveaux Strait between Bluff and Stewart Island.
When he died, he was preparing to swim Cook Strait next month, by notching up 30km to 50km a week in the pool.
Bankers Association chief executive Kirk Hope said Mr Evans was greatly admired for his leadership and longstanding contribution to the banking and finance sectors.
"He led with integrity, vitality and a passion for people,'' Mr Hope said.
"On a personal level, I have always appreciated his collegiality, and hold a deep respect for his personal achievements and professional experience.''
He said Mr Evans' "positive energy and tenacity'' would be greatly missed.
During his time as SBS chief executive, Mr Evans focused on increasing the bank's market presence, its profile in the community, its social media presence and staff training.
As part of the plan to gain recognition in the important North Island markets, SBS had employed mobile mortgage managers to spread the word on what SBS could offer.
Mr Evans leaves behind four sons, aged 14 to 24, and his wife Nicola.
In a profile interview with the Business Herald just before Christmas, he said as an avid long-distance swimmer, pushing himself physically helped relieve stress.
"The job I've got is quite a cerebral one and it's great to be able to relieve some stress through a physical outlet,'' he said.
He said of his family: "If you think about life's achievements, something I'm immensely proud of is my boys - they're resilient, self-reliant, intelligent and articulate people who engage with people quite readily.
"I think I've done my job.''
- Dene Mackenzie with The New Zealand Herald
